O'Neill Cylinder

An O'Neill cylinder is a concept for a massive space habitat proposed by physicist Gerard K. O'Neill in the 1970s. It consists of two counter-rotating cylinders, each several kilometers long and a few kilometers in diameter, that rotate around their longitudinal axis to create artificial gravity through centrifugal force. The interior of the cylinder is designed to support a self-sustaining human population with Earth-like living conditions.
https://www.projectrho.com/public_html/rocket/spacecolony.php